This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Sympathetic nervous system overactivity is a common factor to obesity, sleep disordered breathing and insulin resistance which predispose to the emergence of metabolic syndrome, that is becoming more prevalent in children, increasing the risk for future onset of cardiovascular disease or cancer. Therefore, the overall goal of this study is to elucidate the relationship between autonomic dysfunction and insulin resistance in obese children with sleep disordered breathing. A unique aspect of this project is that metabolic and autonomic function will be assessed comprehensively in each of the subjects using dual minimal models one for insulin-glucose regulation and the other characterizing cardiovascular autonomic control, that together will also be analyzed with nocturnal episodic hypoxia and sleep fragmentation of sleep disordered breathing. The knowledge derived from this study may ultimately be useful in developing techniques for early detection of autonomic and metabolic abnormalities, as well as less costly and more easily applied methods for detecting sleep disordered breathing in children.